Effect of Hyperbaric Micro-Oxygenation on the Chromatic Evolution of Tempranillo Red Wine

Introduction: Color is one of the most important quality attributes of red wines, as it is closely related to phenolic extraction, anthocyanin stability, oxidation reactions, and consumer perception. Oxygen management during vinification plays a decisive role in the formation and stabilization of red wine pigments. In this context, hyperbaric micro-oxygenation may represent an innovative non-thermal strategy to improve oxygen dissolution and promote controlled reactions involved in color development. This study evaluated the effect of hyperbaric micro-oxygenation on the chromatic characteristics and total phenolic content of red wine produced from Vitis vinifera L. cv. Tempranillo.

Methods: Tempranillo grapes were vinified under controlled conditions. Wines subjected to hyperbaric micro-oxygenation were compared with untreated control wines produced under conventional conditions. Color evolution was assessed using CIELAB coordinates, including lightness (L*), red-green coordinate (a*), yellow-blue coordinate (b*), chroma (C*), hue angle (hab), and total color difference (ΔE). In addition, the total phenolic content was determined to evaluate the effect of the treatment on the extraction and preservation of phenolic compounds. These parameters were used to determine the impact of the treatment on color intensity, red tonalities, chromatic stability, and phenolic composition during the winemaking process.

Results: Hyperbaric micro-oxygenation promoted a differentiated chromatic evolution compared with the control treatment. Treated wines showed a more intense red color, higher chroma values, and greater total color differences, indicating a more pronounced visual evolution of the wine matrix. In addition, treated wines exhibited a slightly higher total phenolic content than the control. The increase in redness, color saturation, and phenolic content suggests that the treatment may favor anthocyanin extraction, reduce phenolic oxidation, promote pigment stabilization, and enhance the formation of more stable phenolic complexes under controlled oxygen availability.

Conclusions: Hyperbaric micro-oxygenation may be considered a promising technological tool to modulate and improve the chromatic quality of Tempranillo red wines. Its application could contribute to enhancing color intensity and stability while promoting a slight increase in total phenolic content, supporting its potential use in innovative red winemaking strategies.